Adhesive type closure arrangements have been used to seal and/or close plastic bags such as those used for sandwiches, garbage containers, and the like.
U.S. Pat. No. 4,519,095 to Clayton describes a resealable flexible thermoplastic bag wherein the closure comprises at least one female channel member or strip affixed to the bag and having a pressure sensitive adhesive (PSA) layer on an internal portion of the channel strip. During shipment and storage the walls of the channel hold the pressure sensitive adhesive layer away from adjacent surfaces to prevent inadvertent sticking. Sealing of the bag is achieved by contacting the channel strip with a surface of the bag and exerting pressure along the strip whereby the pressure sensitive adhesive is contacted with a substantially flat portion of the surface and adhered thereto.
Clayton also describes a resealable plastic bag containing a channel with the adhesive layer positioned on a flap of the bag, a channel with the adhesive positioned on the body of the bag over which the flap will fold, and two female channel strips positioned on opposite sides of a bag opening to affect a double seal by pressing the two channels into contact such that one wall or bead of each channel is contacted by the adhesive layer in the opposing channel.
U.S. Pat. No. 6,502,986 to Bensur et al. describes a product package with a resealable end closure. The package is heat-sealed to form permanent fin-seals at its end closure, where the ends of a flexible sheet are heat-sealed together and the sheet may contain one or more layers. A resealable seal is formed adjacent to the permanent seal at one end of the package. The resealable seal is formed by a PSA placed on a first interior region of the package. The PSA is covered with a heat seal coating. Another heat seal coating is applied to a second interior region of the package. The two interior regions with the heat seal coatings are then sealed to form an initial resealable seal. Upon opening the package from the end seal adjacent to the initial resealable seal, and pulling apart the resealable seal, the PSA dislodges from the first region and stays with the second region. The package is resealed by pressing the second region against the first region.
U.S. Pat. No. 5,089,320 to Straus et al. describes a resealable package where a PSA layer is coated onto a substrate layer used for flexible packaging. The adhesive layer may be coated only in the area where the package is to be opened or may be coextruded with the substrate layer throughout the film, and is further covered by and/or coextruded with a skin layer placed over the adhesive layer. The package is sealed to itself and when it is opened at the adhesive layer area it is broken apart at the skin layer, thus exposing the adhesive, either between the adhesive and skin layer, or between the substrate and adhesive, or both. The skin layer seals to itself, thus forming a fin seal arrangement.
U.S. Pat. No. 8,091,323 to Paterson describes a reclosable film structure for a package, in particular a reclosable lap seal, containing a multiple layer film with an interior PSA layer. The PSA layer is positioned between a first and a third layer on either side of the PSA layer and is continuous throughout the package. The package is heat sealed at an open end to initially close the package by folding over an outer lap seal segment onto an inner lap seal segment and heat-sealing together. Upon opening the package at the lap seal, the package delaminates between the first and second layers along one of the lap seal segments, thus exposing the pressure sensitive adhesive layer to facilitate reclosing the package. The exposed PSA is oriented away from the package interior and away from the food removal path to maintain the adhesion strength by avoiding food contact.
U.S. Pat. No. 7,963,413 to Sierra-Gomez et al. describes a container for a food product including a tamper-evident closure which forms an opening of a container. The closure contains a sealing layer, adhesively sealed to the top of the container around the opening. The sealing layer is releasable from the container by pulling back on the sealing layer and resealable against the top layer to seal the opening when the sealing layer is moved back against the top.
All of the packaging materials described above use a PSA as part of the adhesive and/or resealing system. The integrity of the pressure sensitive adhesive can be compromised when the food in the packaging contacts the adhesive. Attempts to overcome this include orienting the PSA away from the interior of the package. However, foods that produce crumbs, such as cookies, crackers, potato chips, etc. are still likely to adhere to the PSA compromising the adhesive system. PSA binding is also not selective; the PSA can adhere to potentially any surface of the package or contents of the package. Finally, the strength of the adhesion of the PSA decreases over time due to adhesive transfer.
There exists a need for an improved system for resealing articles that overcomes the limitations of PSA systems including contamination of the adhesive system by food or other consumer materials non-selectivity, diminished peel strength with reuse, and adhesive transfer.
Therefore, it is an object of the invention to provide improved resealable packaging materials, in particular, food packaging and other consumer packaging.
It is another object of the invention to provide a method for using improved resealable packaging materials, in particular, food and other consumer packaging.
It is another object of the invention to provide a kit for preparing improved resealable packaging materials, in particular, food and other consumer packaging.